JEE Main 2021 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 24 February 2021, Shift 1, Chemistry Q57

Question 57 of 90 in this shift, Chemistry question 27 of 30, Section B.

The reaction of sulphur in alkaline medium is given below :

\mathrm{S_{8(s)} + a\ OH^-_{(aq)} \longrightarrow b\ S^{2-}_{(aq)} + c\ S_2O_3^{2-}{}_{(aq)} + d\ H_2O_{(l)}}

The values of ‘a’ is __________. (Integer answer)

Official answer

NTA final key.

Chapter: Redox Reactions
Topic: Redox Reactions
Idea tested: Ion-Electron Basic

Same topic in other shifts

All Redox Reactions questions

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.